The present invention relates to an interconnector and a solar panel.
Japanese Laid-Open Patent Publication No. 2005-191479 discloses a prior art solar panel. The solar panel includes a protection cover, a back cover, a first photovoltaic cell, a second photovoltaic cell, an interconnector, and an encapsulation member.
The protection cover is formed by an inorganic glass and transparent from an upper surface to a lower surface of the protection cover. The back cover is formed by a resin film or the like. The first photovoltaic cell and the second photovoltaic cell are located adjacent to each other in a first direction. More specifically, the first photovoltaic cell is located at one side in the first direction. The second photovoltaic cell is located at the other side in the first direction.
The interconnector is flat. The interconnector is located between the first photovoltaic cell and the second photovoltaic cell to be parallel to the first photovoltaic cell and the second photovoltaic cell. The interconnector includes a first electrode connected to the first photovoltaic cell, a second electrode connected to the second photovoltaic cell, and a joint that connects the first electrode and the second electrode. The first photovoltaic cell, the second photovoltaic cell, and the interconnector, which are located between the protection cover and the back cover, are encapsulated and fixed to one another by the encapsulation member.
In the solar panel, the first photovoltaic cell and the second photovoltaic cell, which are adjacent to each other in the first direction, are electrically connected to each other by the interconnector.
This type of solar panel may be expanded and contracted by changes in the temperature that occur when the solar panel is manufactured or used. This changes the interval between the first photovoltaic cell and the second photovoltaic cell, which are adjacent to each other. Therefore, when the interval of the first photovoltaic cell and the second photovoltaic cell is narrowed by the contraction of the solar panel caused by changes in the temperature, the first photovoltaic cell and the second photovoltaic cell apply a compression load to the interconnector. More specifically, the interconnector is pressed by the first photovoltaic cell and the second photovoltaic cell from opposite sides. Such a load may break the interconnector in a thickness-wise direction. When the interval between the first photovoltaic cell and the second photovoltaic cell is widened by the expansion of the solar panel caused by changes in the temperature, the first photovoltaic cell and the second photovoltaic cell apply a tension load to the interconnector. More specifically, the interconnector is pulled by the first photovoltaic cell and the second photovoltaic cell from opposite sides. This may separate the first electrode from the first photovoltaic cell or the second electrode from the second photovoltaic cell.
Consequently, in the solar panel, the first photovoltaic cell and the second photovoltaic cell may be electrically disconnected from each other. Particularly, when the protection cover and the back cover are formed from a resin, the protection cover and the back cover each have a large thermal expansion coefficient. Thus, the above problem becomes more prominent.